The use of CLAs to provide power to a wide variety of apparatus is known. Typically, such CLAs are provided with a body portion and a barrel portion on which are provided the electrical contacts. A first contact pin protrudes from the end of the barrel portion, and one or more second contacts are provided on the cylindrical periphery of the barrel portion such that when the CLA is inserted into the cigarette lighter of a vehicle, an electrical circuit, including whatever electronics are provided inside the CLA, is completed, and power can be drawn from the vehicle battery. Usually, vehicle batteries provide a 12V DC power source, whereas the majority of electronic apparatus which might be used in a car will require slightly different, albeit still low, voltage. Examples of apparatus include laptop computers, in-car DVD players, mobile telephones, and in-car or portable navigation devices, with which this invention is primarily concerned. Power is provided to the apparatus by means of a cable which is electrically connected internally to the electronics inside the CLA, and which emerges from the rear or side of the body of the CLA, ultimately terminating in a suitable connector.
Personal navigation devices or PNDs are being widely adopted by drivers and owners of vehicles throughout the world. The navigation assistance provided by such devices is facilitated by on-board processing equipment which accurately (within about 10 m) determines the position of the PND on the surface of the earth, and associates that position with digitized map data provided in memory accessible to the PND, usually either in a small memory card, or on-board RAM or ROM. As is known, PNDs can receive user input of a desired destination in a variety of ways, whereupon the PND calculates a best route according to various algorithms and user requirements and then displays a relevant portion of a map along with a route to be navigated. Typically the PND will include an internal battery, but as most PNDs include a display screen for real-time display of map data as the vehicle moves, they are relatively power-hungry devices and can only be used on battery power alone for short journeys.
CLA adapters which provide power for PNDs, and for re-charging the batteries within them, are known. Currently, CLAs are aftermarket accessories which provide only power to the PND thereby having limited market value, especially when competing with home chargers and other charging devices. Accordingly, a need exists in the art for a more cost effective, functional and consumer-appealing CLA.
Published US patent application US2005/0054400 discloses a CLA which is in the traditional form having a barrel portion with contacts and a body. Within the body there is further provided a first circuit for power management, regulation, and delivery to a first output, and one or more further circuits, powered from the contacts, capable communicating in a wireless local area network (WLAN). An antenna is further provided in the body, the signal from said antenna being delivered to the WLAN circuitry, a separate output for which is also provided. Both outputs are in the form of two or more cables emerging from the rear of the body of the CLA, for separately providing a recharging power source, and telecommunications data derived from the signal received by the antenna within the device.